There are several known approaches to the problem of electronic wakeup initiated by the receipt of a radio frequency (RF) signal. However, the known approaches suffer various drawbacks. These include (depending on the particular approach) a necessary power draw of more than a microwatt to monitor for low-level signals, a need for duty cycling, a tradeoff that sacrifices sensitivity in favor of lower power dissipation, and a need for relatively high power levels to self-power the wake-up stage.
Accordingly, there remains a need for RF wakeup devices that combine high sensitivity with extremely low quiescent power dissipation.